Door latching assembly

ABSTRACT

A latching assembly for attachment to a door frame and including a housing and a latch bolt. The bolt is connected at one end to a part of the housing to allow the bolt to swing in a horizontal plane between latched and unlatched positions. Additional reinforcing means is provided to resist forces tending to move the bolt across the door frame whereby the assembly can be lightly and inexpensively constructed.

United States Patent [191 McBurnie et al.

[111 3,811,719 [451 May 21, 1974 DOOR LATCHING ASSEMBLY- [75] Inventors:Stuart G. McBurnie, Burnaby,

British Columbia; William A. W. .lorgensen vy t \iancouver, BritishCofimbfa; Michel L. E. Rachel, Vancouver, British Columbia, all Canada[73] Assigneez' Velto Industries, Ltd., Vancouver,

British Columbia, Canada [22] Filed: Nov. 30, 1972 [2]] Appl. No.:310,803

[52] US. Cl 292/254, 292/219, 292/341.l7

51 rm. Cl. E05c 1/08 [58] Field of Search 292/254, 191, 192, 341.17,

4 i Y 292/227, 2l9, 220, DIG. 38

[ 56] References Cited UNITED STATES PATENTS 30,594 ll/l860 Slaight292/191 6/1886 Taylor.....; 292/254 2/l897 Voight 292/192 l/l963McBurnie 292/254 Primary Examiner-Richard E. Moore Attorney, Agent, orFirm-Fetherstonhaugh & Co.

ABSTRACT 6 Claims, 8 Drawing Figures 1 DOOR LATCI-IING ASSEMBLY Thisinvention relates to a latching assembly for the latch or lock sets ofinterior or exterior doors.

It has been suggested previously that latch bolts be mounted in doorjambs rather than in the edges of the doors but this type ofconstruction has a number of disadvantages which may explain why thearrangement has not found wider acceptance. For example, the bolt andhousing therefor must be exceptionally strong otherwise it is not toodifficult for a burglar to force open the door by appl ing his weight tothe door or using a jimmy since it is the latch bolt itself which musttake the major part of the stress involved.

The present assembly is made, with the exception of the spring and thescrews which secure the device to the door jamb, entirely of plastic sothat it can be relatively inexpensively produced to operate quietly foryears without the need for lubrication. It is an extremely simple matterto snap the latch bolt into its supporting housing and, once properlyassembled, the pivoted end of the latch bolt is relieved of any need toresist forces tendingto move the bolt towards the interior of the room.This reinforcing of the latch bolt is achieved by means of ribs andco-operating channels formed on the bolt and the housing respectivelyand both of which are curved to allow the latch bolt head to swing in anarcuate path.

In drawings which illustrate a preferred embodiment of the invention,

FIG. 1 is a horizontal section of a door and door jamb, showing inposition of use, a door latching assembly in accordance with the presentinvention,

FIG. is a perspective view of the assembly,

FIG. 3 is a horizontal section taken on the line 33 of FIG. 2,

FIG. 4 is a front elevation of a housing which forms part of theassembly,

FIG. 5 is a perspective view of a latch bolt also forming part of theassembly,

FIG. 6 is an enlarged horizontal section of the housing taken on theline 66 of FIG. 4,

FIG. 7 is an enlarged plan view of the latch bolt, with part broken awayand shown in section, and

FIG. 8 is a fragmentary vertical section taken on the line 8-8 of FIG/6.f

Referring first to FIG. 1 of the drawings, the numeral 10 indicatesgenerally adoor frame which includes a jamb 11 having a side edge 12which is fitted with 'an abutment strip 14. A door 17 is adapted to behung in the frame 10 to close against the strip 14; the door having anoutside'face 18, an inside face 19, and a side edge 20 opposite thehinged edge (notshown) of the door. 1 The assembly for latching the doorwithin the bordering frame 10, and which forms the basis of the presentinvention, is generally indicated by the numeral 30 and comprises ahousing 31 for a spring-pressed latch b'olt 32. The side edge 20 of thedoor is recessed to receive a suitably attached'strike 35 having a hole36-which is centered in a tapered recess 37 formed in the exposed faceof the strike. The recess 37 provides a vertical stop 38 near theoutside face 18 of the door, the stop being engaged by the latch bolt 32whereby to hold the door latched. The door handles (not shown) areadapted to operate a latch bolt releasing plunger 40 which is mounted inthe door to project through 'a hole 41 so that the outer end of saidplunger normally is enclosed by the hole 36. A spring 42 encloses aportion of the plunger 40 between a collar 43 and the strike 35 wherebyto exert a resilient force normally holding said plunger in retractedposition. Thus, the latch bolt 32 can be dislodged from latchingengagement with the stop 38 by giving a partial turn to either handleknob so as to extend the plunger 40 and push said latch bolt out of therecess 37.

Generally speaking, the above described arrangement .of parts can befound in other latch or lock sets but the present door latching assembly30 has a number of features and advantages which make it unique andthese will now be described. The housing 31 is formed of a tough plasticmaterial such as nylon rather than the usual metal and this ensures aparticularly smooth and quiet latching and unlatching action. As shownbest in FIGS. 3 and 4, the substantially oblong housing 31 has an innerwall 50, sidewalls 51 and 52, as well as top and bottom walls 53 and 54.A flange-like face plate 56 is integrally formed with the four walls ofthe housing 31 and this plate is provided with vertically spaced holes57 one of which is shown in FIG; 4. Frame 10 is assumed to be of woodconstruction but it should be noted the present assembly can be usedequally as well on metal door frames. Assembly 30 is designed to fitinto the standard size openings which are routed and/or stamped inconventional wood and metal frames. In order to fit the housing 31 tothe jamb 11, an opening 60 and recess 61 (see FIG. 3) are cut in theside edge 12 to receive said housing and the face plate 56 respectively.Metal screws 62 (FIG. 4) are then entered through the holes 57 to securethe plastic housing 31 to the wood jamb 11.

The face plate 56, which preferably is rectangular as shown in FIG. 4for wood door frames, is provided with a centrally disposed slot 66, seeparticularly FIG. 4. This rectangular slot 66 connects with the interiorof the housing 31 and has side edges 67 and 68 as well as top and bottomedges 69 and 70. The spacing between edges 69 and 70 is the same as thespacing between the opposing inner surfaces of the housingwalls 53 and57. Edge 67 is a continuation of the inner surface of the wall 51. Sideedge 68 is spaced a short distance from and extends parallel to insideedge 72 of the face plate 56.

The latch bolt 32 carried by the housing 31 is formed of the same tough,glass-filled, plastic nylon and, as shown best in FIGS. 3 and 5 to 7,the bolt has a hollow head 74 and a shank 75 which are generallyrectangular to closely fit the slot 66. The oblong head 74, which issubstantially perpendicular to the shank-75, has sidewalls 76 and 77, aswell as top and bottom walls 78 and 79. Outer face 80 of the latch bolt32'is suitably shaped toprovide a cam face for the end of the plunger 40and the head has'a flattened portion 81 normal to the longitudinal axisof the shank, which portion is adapted to abut the stop 38 on the striketo latch the door. The plastic bolt 32 is slightly resilient and thedegree of resilience is increased by the shaping of the shank 75particularly near the junction of the head 74 and said shank. In otherwords, the shank 75 is thinned down and offset slightly relative to thehead 74 so that it or the head can flex slightly if necessary and in theplane of the longitudinal axis of said shank.

The latch bolt 32 is swingingly mounted on the housing 31 by pivot meansgenerally indicated at 85, see

FIGS. 3 and 5 to 7. Means 85 is shown to comprise a pair of pintles 87which are formed on top and bottom edges 88 and 89 of the shankalongside end edge 90 thereof. The housing 31 portion of the pivot meansis shown best in FIGS. 4 and 6 to comprise an arrangement of flangeswhich are provided on the face plate 56 at side edge 68 of the housingslot 66. Upper and lower flanges 92 and 93 are formed in the comers ofthe slot 66 and these flanges are coplanar with the face plate 56. Anintermediate flange 94 formed on the edge 68 is faced inwardly of theflanges 92 and 93 to provide a socket 95.

The pivot means 85 is particularly easy to assemble and this is donesimply by entering end edge of the shank 75 into the socket from theface plate side of the housing 31. Pintles 87 are lodged behind theflanges 92 and 93 while the intermediate flange 94 forms a stop for theend edge 90 which holds said edge within the socket 95. When the head 74is pushed into the interior of the housing 31, the latch bolt 32 cannotmove so as to withdraw the edge 90 from the socket 95 and the bolt ispivotally mounted in the housing 31 so that it can swing from a latchedto an unlatched position and return.

The door latching assembly 30 is provided with spring means intended tobias the latch bolt 32 towards the latched position and this means isshown in FIG. 3 to comprise a compression spring 98. One end of the coilspring 98 fits over a boss 99 formed on the wall 50 of the housing whilethe opposite end of said spring is lodged between inwardly directedflanges 100 formed on each of the four walls of the head 74. Thus, thespring 98 can curve about an are centered on the axis of swing of thelatch bolt 32 which, of course, coincides with the vertical axis of thepintles 87.

The lightly but sturdily constructed latch bolt 32 at times can berequired to take a considerable amount of stress such as would occur ifan attempt was made to 'force the door 17 open without operating thedoor handles or unlocking the set in a proper manner. Normally, thepivoted end of the latch bolt would have to be made heavy and thereforstrong enough to take this stress but the present assembly 30 includesguide means which support the latch bolt 32 as it swings about the pivotmeans 85 between its latched and unlatched positions. As shown in FIGS.4 to 5 and in FIG. 8, the means 105 comprises a pair or arcuate ribs 106which are integrally formed one on each of the top and bottom walls ofthe head 74. These ribs 106 are received within a pair of similarlycurved channels 107 which are formed on the inner surfaces of the walls53 and 54 of the housing. Thus, the latch bolt 32 is firmly supportedwithin the slot 66 and the pivot means 85 is properly reinforced and isnot required to take any amount of stress if the door is forced inwardlywithout turning the handles.

Incorporated into the guide means 105 is stop means 110 which limitsoutward swinging movement of the latch bolt. In FIGS. 5, 6 and 8, thestop means 105 is shown to comprise a pair of bosses 112 which areformed one on each of the ribs 106 near the inner end of the head. Thebottoms of the channels 107 are deepened to provide slots 114 into whichthe bosses 112 project and these slots terminate at their outer ends ina shoulder 115. When the latch bolt 32' is swung outwardly, the bosses112 engage the shoulders 115 to halt further outward movement.

It will be noted that, in order to insert the head 74 into the housing31, the bosses 112 must be sprung over the shoulders 115. This can onlybe done after the pivot means has been assembled as previously describedsince only then are the bosses 112 properly aligned with the slots 114.Some force is required to snap the bosses 112 over the shoulders 115and, at the same time, to partially compress the spring 98 which must beinstalled first but, once the assembly has been made, there is littlelikelihood of the latch bolt 32 being accidentally discahrged from thehousing 31.

As mentioned previously, the latching assembly 30 can be used on factoryprepared wood or metal door frames the tolerances of which may varyslightly from one installation to the next. At times when a door ishung, it will be found that it is a very tight fit within the framewhich might not leave sufficient clearance between side edge 20 of thedoor and the adjacent side edge 12 of the frame for a conventional latchset or the like to operate properly. The latch bolt 32 will compensatefor this tight fit to some extent at least by virtue of its slightresilience and the shape given to the shank 75. The strike 35 may pressthe bolt 32 further into the housing 31 than usual in the case of atight fit but the angular relationship between the head and shank of thebolt allows the flattened portion 81 to project outwardly far enough toenter the recess 37 and engage the stop 38. Normal turning pressureapplied to either door handle knob will project the plunger 40 to springthe bolt 32 out of latching engagement with the strike 35 and the shank75 may be flexed slightly near the head 74 as this unlatching actiontakes place. Thus, the assembly 30 will function properly if clearancebetween the door and jamb is less'than desired and, of course, thespring 98 will fully extend the latch bolt to ensure proper operation ifthe clearance is greater than normal.

From the foregoing, it will be apparent there is provided a doorlatching assembly which is relatively inexpensive to manufacture andwhich can readily be as sembled by almost anyone without the use ofspecial tools. The guide means for the latch bolt strengthen theassembly where reinforcement is needed and relieves the pivot means of amajor portion of any load tending to move the latch bolt transversely ofthe face plate.

We claim:

1. A door latching assembly comprising a housing adapted to be mountedwithin an opening formed in a side edge of a door jamb, said housinghaving a face plate securable to the side edge, said face plate having atransversely extending slot communicating with the interior of thehousing, a latch bolt mounted in the slot and having a head at one endthereof movable within the housing, pivot means connecting an end edgeof the latch bolt remote from the head to the face plate whereby saidlatch bolt can swing between a latched and an unlatched position, springmeans biasing the latch bolt outwardly of the housing, stop meanslimiting outward swinging movement of the latch bolt, and guide meansbetween the head and adjacent edges of the slot for relieving the pivotmeans of a major portion of any load tending to move the latch bolttransversely of the face plate.

2. A door latching assembly as claimed in claim 1, in which said housingand said head have opposing side walls, said guide means comprising arib on one of the side walls and a channel on the other of said sidewalls in which said rib is slidably received, said rib and channel beingcurved about an are having a centre coinciding with the axis of swingprovided by the pivot means.

being partly defined by opposing flanges and an intermediate flange,said opposing flanges engaging the pintles and said intermediate flangeengaging an opposite side of the end edge.

5. A door latching assembly comprising a housing adapted to be mountedwithin an opening formed in a side edge of a door jamb, said housinghaving a face plate securable to the side edge, said face plate having atransversely extending slot communicating with the interior of thehousing, a latch bolt mounted in the slot and having a head at one endthereof movable within the housing, pivot means connecting an end edgeof the latch bolt remote from the head to the face plate whereby saidlatch bolt can swing between a latched and unlatched position, springmeans biasing the latch bolt towards the latched position, said housingand said head having opposing side walls, a rib on one of the side wallsand a channel on the other of said side walls in which said rib isslidably received, said rib and channel being curved about an arc havinga center coinciding with the axis of swing provided by the pivot means,a boss on the rib and a co-operating shoulder at the end of the channeladjacent the face plate.

6. A door latching assembly as claimed in claim 5, in which the housingand the latch bolt are made of plas-

1. A door latching assembly comprising a housing adapted to be mountedwithin an opening formed in a side edge of a door jamb, said housinghaving a face plate securable to the side edge, said face plate having atransversely extending slot communicating with the interior of thehousing, a latch bolt mounted in the slot and having a head at one endthereof movable within the housing, pivot means connecting an end edgeof the latch bolt remote from the head to the face plate whereby saidlatch bolt can swing between a latched and an unlatched position, springmeans biasing the latch bolt outwardly of the housing, stop meanslimiting outward swinging movement of the latch bolt, and guide meansbetween the head and adjacent edges of the slot for relieving the pivotmeans of a major portion of any load tending to move the latch bolttransversely of the face plate.
 2. A door latching assembly as claimedin claim 1, in which said housing and said head have opposing sidewalls, said guide means comprising a rib on one of the side walls and achannel on the other of said side walls in which said rib is slidablyreceived, said rib and channel being curved about an arc having a centrecoinciding with the axis of swing provided by the pivot means.
 3. A doorlatching assembly as claimed in claim 2, in which said stop meanscomprises a boss on the rib and a co-operating shoulder at the end ofthe channel adjacent the face plate.
 4. A door latching assembly asclaimed in claim 1, in which said pivot means comprises oppositelydirected pintles on the end edge of the latch bolt, said face platehaving a socket to receive the end edge, said socket being partlydefined by opposing flanges and an intermediate flange, said opposingflanges engaging the pintles and said intermediate flange engaging anopposite side of the end edge.
 5. A door latching assembly comprising ahousing adapted to be mounted within an opening formed in a side edge ofa door jamb, said housing having a face plate securable to the sideedge, said face plate having a transversely extending slot communicatingwith the interior of the housing, a latch bolt mounted in the slot andhaving a head at one end thereof movable within the housing, pivot meansconnecting an end edge of the latch bolt remote from the head to theface plate whereby said latch bolt can swing between a latched andunlatched position, spring means biasing the latch bolt towards thelatched position, said housing and said head having opposing side walls,a rib on one of the side walls and a channel on the other of said sidewalls in which said rib is slidably received, said rib and channel beingcurved about an arc having a center coinciding with the axis of swingprovided by the pivot means, a boss on the rib and a co-operatingshoulder at the end of the channel adjacent the face plate.
 6. A doorlatching assembly as claimed in claim 5, in which the housing and thelatch bolt are made of plastic.